Bone Health and Calcium
1. What is Calcium?
Calcium is the most important mineral in the body, the bones and teeth contain 99% of the calcium in your body. The remaining 1% is presented in blood, extracellular fluid, muscle, and other tissues. Calcium is essential for the heart, muscles and nerves to function properly and for blood to clot, it is also essential for respiration, renal function, vascular contraction, vasodilation, glandular secretion, cell membrane and capillary permeability, enzyme reactions, and neurotransmitter and hormone release and storage (1).
Each day, you lose calcium through your skin, nails, hair, sweat, urine and feces. Your bodies cannot produce calcium. That's why it's very important to get enough calcium from the foods you eat.
When you don't get enough calcium for your body's needs, calcium is automatically taken from your bones. This can make your bones weak and break easily.
2. Poor Bone Health is Common and Costly
According to the US Surgeon General's Report 2004 on Bone Health and Osteoporosis, approximately 34 million Americans have reduced bone mass and ten million have osteoporosis. Half of women and one quarter of men over the age of 50 will have osteoporosis-related fracture sometime during their lifetime. According to US NOF (National Osteoporosis Foundation), by 2020, 61 million Americans will have low bone mass and osteoporosis (2).
1.5 million people are hurt each year in US due to fractures from osteoporosis.
500,000 people are hospitalized each year due to osteoporosis.
800,000 people make trips to the emergency room due to osteoporosis.
2.6 million people make visits to the doctor's office due to osteoporosis.
180,000 people are places in nursing homes due to osteoporosis (2).
3. Weak Bones Hurt Us All
Broken bones are very painful at any age. Each year 1.5 million older people in USA will suffer fractures because their bones have become weak. For older people, weak bones can be deadly.
If you are elderly, a broken hip makes you four times more likely to die within three months. If you survive the injury, it often causes your health to spiral downward. One in four people with hip fracture die within first year, and one in five people with a hip fracture will ends up in a nursing home within a year. Many others become isolated, depressed, or frightened to leave home because they fear they will fall.
The cost of weak bones to Americans, their families, and our country is huge. The medical expense for treating broken bones from osteoporosis is as high as $18 billion each year. The cost of care for these patients and the work that is lost adds billions more (2).
4. Why Common Calcium Supplements Do Not Help?
Many calcium supplement are formulated with a variety of salts including calcium carbonate, calcium citrate, calcium lactate, calcium gluconate, and calcium phosphate. The selection of a calcium supplement should be determined by a number of factors, including absorbability, bioavailability, tolerance, solubility in the intestine, and side effects.
Most forms of supplemental calcium have three disadvantages:
1. Low solubility and or low absorbability.
Most calcium supplements have very low absorbability, such as calcium carbonate (the most common calcium form), it is not water soluble and has very low absorbability; another calcium form such as calcium citrate is water soluble, but it still has very low absorbability. Why? Because most forms of supplemental calcium have something in common: They have to produce calcium ions in order to be absorbed in the small intestine. The PH of the small intestinal fluid is 7.0-7.2. At this PH, most calcium ions will form insoluble hydroxides, a gelatinous type of precipitation. It also can form insoluble complexes with substances commonly presented in food, such as phosphates, oxalates, and phytates. This is why most calcium supplements have low absorbability (5).
"The effective absorption of inorganic minerals is generally less than 10%". (5)
2. Low bioavailability.
Most forms of supplemental calcium have to produce calcium ions in order to be absorbed in the small intestine. The calcium ions are absorbed through ion channel in the small intestine, after calcium ions are absorbed to the blood, these ion form of calcium can be secreted through urine and sweat. That is why most common calcium supplements have low bioavailability.
3. Side effects such as: constipation, bloating, destroys vitamins and blocks other nutrients absorption.
Almost all calcium supplements produce calcium ions in order to be absorbed.
One problem is that the calcium ions will form insoluble precipitation with hydroxides, phosphates, oxalates, and phytates which are commonly presented in food. This not only renders the calcium non-absorbable, but also can cause gastrointestinal side effects such as constipation, bloating, and gas due to the coating of the precipitate on the mucous membrane of the small intestine (6).
The other problem is that the mineral ions are catalysts; it can catalyze oxidative destruction of vitamins, and decrease vitamins and its antioxidant effects (5, 6, 7).
This precipitation will absorb other trace nutrients such as trace minerals and vitamins in the small intestine and cause them also to be non-absorbable (5, 6, 7).
5. The Best Calcium Supplement
The most common calcium supplements have three disadvantages: low absorbability, low bioavailability, and side effects. All these disadvantages are caused by the calcium ions in the small intestine, and the common calcium forms have to produce calcium ions on order to be absorbed. To eliminate these problems, Noble Prize winner Alfred Werner mentioned chelated mineral theory many years ago. If mineral ions are chelated with amino acids, they will have 1. High absorbability. 2. High bioavailability. 3. No side effects such as constipation, destroy vitamins and block vitamins and nutrients absorption.
The calcium in MaxCal+ is in the most advanced amino acid chelated form. This amino acid chelated calcium has three advantages:
1. 100% soluble and highest absorbability.
The chelated minerals are especially surrounded and well-shielded by several unique amino acids, the bonds between mineral ions and amino acids are so strong that it will resist any anion attack even at PH 11. Chelated mineral ions can not come out to form precipitate in the small intestine; that is why MaxCal+ minerals always keep soluble and readily absorbable in the small intestine (5, 6, 8, 9, 10, 11, 12, 13).
2. Highest bioavailability.
Calcium in MaxCal+ is actively absorbed in the body by passing through special amino acid channel in the small intestine. This absorption is very fast and effective, and after MaxCal+ is absorbed to the blood, the calcium in MaxCal+ is still be chelated with amino acids and it will not be secreted to the urine and sweat. That is why MaxCal+ has highest bioavailability (9, 10).
3. No side effects such as: constipation, bloating, destruction of vitamins and blocking of nutrient absorption.
The minerals in MaxCal+ are in a special amino acid chelated form. These chelated mineral ions can not come out to form precipitate in the small intestine. They will not block other trace minerals and vitamins from absorption, and will not cause constipation, bloating, gas or other side effects (5, 6, 8).
Because this chelated mineral ions can not come out to catalyze oxidative destruction of vitamins. MaxCal+ will preserve vitamin's stability and antioxidant effects (5, 6).
6. Comparison of Different Calcium Forms
7. Tips for maintaining strong bones:
8. Scientific Reports about Calcium
Build Healthy Bones. Taking calcium orally is effective for preventing and treating bone loss and osteoporosis. Multiple clinical studies and meta-analyses suggest efficacy for calcium plus vitamin D for primary prevention of osteoporosis ((14, 15,16,17,18, 19, 20, 21, 22) *.
Bone loss is more pronounced if dietary calcium intake is below the RDA, which is the case for many. (23, 24) *.
Bone loss in premenopausal women over age 40 can be reduced significantly by supplementing with 1000 mg calcium/day (24) *.
The typical rate of bone loss in postmenopausal women who are not taking calcium supplements is 2% per year (25, 26).
Calcium 1000-1600 mg/day decreases this rate by 0.25% to 1% annually (27, 28, 29, 30, 23, 25, 31, 26, 24, 32) *.
30 years of continuous calcium supplementation after menopause might result in a 50% overall reduction in fracture rates, compared with women who do not take calcium supplements. (33) *.
Most studies show that long-term calcium supplementation decreases primary fracture rates for specific bones by 30% to 35% for vertebral bone and 25% for hip bone (26) *.
Reduce Diabetes. Some population research suggests that a higher intake of calcium from diet and supplements alone or in combination with vitamin D is associated with a lower risk of developing type 2 diabetes compared to lower calcium intake (34, 35) *.
Reduce Hypertension. Several clinical trials show that taking calcium supplements modestly reduces blood pressure. Calcium seems to be more effective for certain subpopulations of patients, such as salt-sensitive people and patients with low baseline dietary calcium intake (36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47) *.
Population research also suggests that women aged 45 years and older, with higher intake of calcium, seem to have a lower risk of developing hypertension compared to women with lower calcium intake (34) *.
Some clinical research shows that taking calcium orally reduces blood pressure in patients with end-stage renal disease (ESRD) (48) *.
Reduce Breast Cancer. Population research shows that higher intake of calcium is associated with a significantly reduced risk of developing breast cancer in premenopausal women (49) *.
Weight Loss. Adults and children with low calcium intake are more likely to gain weight, have a higher body mass index (BMI), and be overweight or obese compared to people with high calcium intake. (50, 51, 52, 53, 54, 55) *.
According to some analyses of calcium studies, an increase in dietary calcium consumption of 900-1000 mg/day is associated with an 8-9 kilogram reduction in body weight in adults (50, 54) *.
Lower Cholesterol. Taking calcium supplements in conjunction with a low-fat or calorie-restricted diet might modestly reduce cholesterol (56) *.
Reduce any Type of Cancer. A clinical trial shows that healthy postmenopausal women who take supplemental calcium 1400-1500 mg/day plus vitamin D3 (cholecalciferol) 1100 IU/day have a 60% lower relative risk for developing cancer of any type (57) *.
Reduce Premenstrual Syndrome (PMS). There seems to be a link between low dietary calcium intake and symptoms of PMS. (58).
Taking calcium 1-1.2 grams daily seems to significantly reduce depressed mood, water retention, and pain associated with PMS (59, 60, 61) *.
Reduce Ischemic Stroke. There is some evidence that increasing dietary calcium intake might decrease the relative risk of ischemic stroke in women. (62) *.
Reduce Prostate Cancer. Some research suggests that taking a calcium supplement 1200 mg/day might decrease the risk of developing prostate cancer. (63) *.
Build Healthy Fetal Bone. Calcium supplementation, in pregnant women who have low dietary calcium intake, increases fetal bone mineralization and density. (64, 65) *.
Reduce Corticosteroid-induced Osteoporosis. Taking calcium in combination with vitamin D as adjunctive therapy seems to be effective for reducing bone mineral density loss in people using corticosteroids long-term. (66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77) *.
Reduce Colorectal Cancer. Population studies suggest that high intake of dietary or supplemental calcium seems to reduce the risk of colorectal cancer. (78, 79, 80) *.
Clinical trials also show that taking calcium supplements can reduce the risk of colorectal adenoma recurrence. (81, 82, 83, 84) *.
Help Tooth Retention. Taking calcium and vitamin D orally appear to beneficially affect tooth retention in the elderly population. (85).
Reduce Cramps. There is preliminary clinical evidence that taking calcium 1 gram twice daily can reduce pregnancy-related leg cramps during the second half of pregnancy. (86).
9. How Much Calcium Do You Need Per Day?
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